PROPERTY, PLANT AND EQUIPMENT - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jan. 31, 2019	Jan. 31, 2018
Property, plant and equipment
Property and equipment, gross	$ 31,709	$ 24,324
Less - accumulated depreciation	11,931	9,025
Property, plant and equipment, net	19,778	15,299
Land and improvements
Property, plant and equipment
Property and equipment, gross	863	863
Building and improvements
Property, plant and equipment
Property and equipment, gross	6,000	5,427
Furniture, machinery and equipment
Property, plant and equipment
Property and equipment, gross	17,779	13,531
Trucks and other vehicles
Property, plant and equipment
Property and equipment, gross	4,918	4,293
Project development costs
Property, plant and equipment
Property and equipment, gross	$ 2,149	$ 210

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
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